JP5578796B2 - Oxygen concentrator - Google Patents

Description

  The present invention relates to an oxygen concentrator, and more particularly, to a medical oxygen concentrator capable of compressing captured raw material air and supplying the compressed air to an adsorbent to supply oxygen.

The oxygen concentrator is configured to obtain oxygen by using a pressure swing adsorption method that generates oxygen by using as an adsorbent a zeolite that permeates oxygen in the raw material air and selectively adsorbs nitrogen. Yes.
According to this type of oxygen concentrator, the raw material air taken in is compressed by a compressor as a compression means to generate compressed air, and this compressed air is supplied to an adsorption cylinder containing an adsorbent. Nitrogen is adsorbed on the adsorbent to generate oxygen. The generated oxygen is stored in a tank, and the patient can inhale oxygen using a device such as a nasal cannula by enabling the supply of a predetermined flow rate of oxygen from the tank via a pressure reducing valve or a flow rate setting device. Can do.

If this oxygen concentrator is installed in a place where AC power (commercial AC power) can be used, for example, a home oxygen therapy patient with reduced lung function will be able to safely take oxygen even while sleeping. it can.
In particular, when the home oxygen therapy patient is used while sleeping, it is preferable that the oxygen concentrator generates very little noise. For example, it is desirable that the noise of the oxygen concentrator is less than or equal to the noise level generated from indoor air conditioning equipment.

In addition, oxygen concentrators used for long-term oxygen inhalation therapy, which is effective as a treatment for patients with respiratory diseases such as chronic bronchitis, are generally not portable, so that patients can take them outside. Not configured.
Therefore, when the patient inevitably goes out, for example, while pushing a cart equipped with an oxygen cylinder filled with oxygen in a predetermined container, concentrated oxygen is sucked from the oxygen cylinder. This oxygen cylinder must be filled with oxygen in a dedicated facility.
Therefore, portable and mobile oxygen concentrators have been proposed, and portable and mobile oxygen concentrators include a compressing means that takes in raw air and generates compressed air, and a decompressing means that generates decompressed air. It is equipped with a compressor that can be driven by a battery (see Patent Document 1).

JP 2002-45424 A

In the conventional oxygen concentrator described above, the piston is operated by rotating the output shaft of the motor of the compressor. However, during this operation, load fluctuations applied to the output shaft of the motor occur, and power consumption cannot be reduced. There's a problem.
In particular, in the case of portable and mobile oxygen concentrators, there is a demand for smaller onboard batteries due to demands for weight reduction and miniaturization, and there is also a demand for reduction in power consumption for compressor motors. .
Accordingly, an object of the present invention is to provide an oxygen concentrator capable of reducing power consumption by reducing a load variation applied to an output shaft of a motor during operation.

The oxygen concentrator of the present invention is an oxygen concentrator comprising a compressor that compresses raw material air to generate compressed air, and an adsorbing member that contains an adsorbent that adsorbs nitrogen from the compressed air. A drive motor having an output shaft, and a first pump unit connected to a first end of the output shaft of the drive motor and operating by rotation of the output shaft to suck in raw material air and generate compressed air And a second pump unit connected to the second end portion of the output shaft of the drive motor and operating by rotation of the output shaft to suck in raw material air and generate compressed air. And
Accordingly, the first pump portion and the second pump portion are provided symmetrically on the first end portion and the second end portion of the output shaft, respectively, so that the pump portion is provided on one end portion of the output shaft. Compared with the case where the load is applied, the load fluctuation applied to the output shaft of the motor during operation can be reduced to reduce the power consumption. In particular, in the case of a portable or mobile oxygen concentrator, it is possible to reduce the size of the on-board battery that is required due to the demand for weight reduction and size reduction.

  In the oxygen concentrator of the present invention, the first pump part includes a first head part having a first piston and a second head part having a second piston, and the first head part and the second head. The first piston and the second piston are reciprocally moved in opposite directions, and the second pump part includes a third head part having a third piston and a fourth piston having a fourth piston. And the third head portion and the fourth head portion are arranged to face each other so as to reciprocate the third piston and the fourth piston in opposite directions. . Thereby, since a piston reciprocates in the opposite direction, noise and vibration can be reduced. Since the oxygen concentrator is always used even when the patient goes to bed, for example, it is desirable that the oxygen concentrator is low in noise and vibration.

In the oxygen concentrator of the present invention, in the suction step in which the first pump portion sucks the raw material air, the compression step of compressing the air sucked in by the second pump portion to generate compressed air is performed, and the first pump In the compression step of generating compressed air by compressing the air sucked by the unit, the second pump unit performs a suction step of sucking the raw material air.
As a result, when the first pump unit is in the suction process, the second pump unit is in the compression process, so that a load is applied from the second pump unit to the output shaft of the drive motor, but the first pump unit is compressed. In the case of the process, since the second pump part is an intake process, a load is more applied from the first pump part to the output shaft of the drive motor. As described above, the first pump unit and the second pump unit alternately perform the compression process and the suction process, so that a constant load is applied to the output shaft, and the load fluctuation with respect to the drive motor can be reduced. Thus, power consumption can be reduced. In the oxygen concentrator of the present invention, the drive motor is an AC synchronous motor. As a result, the AC synchronous motor can operate the first pump unit and the second pump unit at the synchronous rotational speed, and can reduce power consumption as compared with the case of using the induction motor, and the structure can be compared with that of the induction motor. Simple.

  The present invention can provide an oxygen concentrator capable of reducing power consumption by reducing a load variation applied to an output shaft of a motor during operation.

It is a block diagram which shows preferable embodiment of the oxygen concentrator of this invention. It is a perspective view which shows the compressor shown in FIG. It is the perspective view which notched a part of compressor shown in FIG. FIG. 3 is a longitudinal sectional view showing an internal structure of the compressor of FIG. 2. It is a figure which shows the external shape of a compressor with a dashed-two dotted line, and shows the introduction path | route and discharge path | route of the raw material air in this compressor with an arrow. It is a longitudinal cross-sectional view which shows the structural example of a 1st pump part and a 2nd pump part. It is a disassembled perspective view which shows the structure of a 1st head part as an example.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram showing a preferred embodiment of the oxygen concentrator of the present invention.
An oxygen concentrator 1 shown in FIG. 1 is a portable (also referred to as portable or mobile) oxygen concentrator as a preferred embodiment. The oxygen concentrator 1 shown in FIG. 1 uses, for example, a compressed aerodynamic fluctuation adsorption method (PSA: positive pressure fluctuation adsorption method) using compressed air as an oxygen generation principle.
In the positive pressure fluctuation adsorption method using only compressed air, only compressed air is sent into the adsorption cylinder to adsorb nitrogen. The positive pressure fluctuation adsorption method has an advantage that the structure of the compressor can be simplified as compared with the positive and negative pressure fluctuation adsorption method (VPSA) using compressed air and reduced pressure air.

  A double line shown in FIG. 1 indicates a pipe serving as a flow path for raw material air, oxygen, and nitrogen gas. A thin solid line indicates power supply or electric signal wiring. The main casing 2 of the oxygen concentrator 1 shown in FIG. 1 is indicated by a broken line, and the main casing 2 is a sealed container that seals elements disposed inside. The main housing 2 is an injection-molded resin product, for example, and is made of a thermoplastic resin having impact resistance. The main housing 2 shown in FIG. 1 has an intake port 2c for introducing raw material air, which is outside air, and an exhaust port 2b for exhausting. A filter 3 for removing impurities in the air is disposed at the intake port 2c, and when the compressor 10 is operated, the raw air passes through the filter 3 of the intake port 2c and the internal piping 4 along the F direction. To be introduced. The raw air is introduced into the compressor 10 via the pipe 4 and compressed to become compressed air, but heat is generated when the raw air is compressed. For this reason, the compressed air discharged from the compressor 10 is cooled by the rotation of the blower fan 5. By cooling the compressed air in this way, the temperature rise of the zeolite, which is an adsorbent that declines in function at high temperatures, can be suppressed, so that it functions sufficiently as an adsorbent for generating oxygen by adsorption of nitrogen. As a result, oxygen can be concentrated to about 90% or more.

  The first adsorption cylinder 108a and the second adsorption cylinder 108b are examples of adsorption members, and are arranged in parallel in the vertical direction. Three-way switching valves 109a and 109b as switching valves are connected to the first adsorption cylinder body 108a and the second adsorption cylinder body 108b, respectively. Of these switching valves, one end of the three-way switching valve 109 a is connected to the pipe 6. Further, the three-way switching valves 109 a and 109 b are connected to each other, and one end of the three-way switching valve 109 b is connected to the pipe 7. The pipe 7 and the pipe 6 are connected to each other. The pipe 7 is connected to the pipe 6 in order to perform a purification process for desorbing unnecessary gas in the first adsorption cylinder body 108a and the second adsorption cylinder body 108b. The three-way switching valves 109a and 109b are connected to the first adsorption cylinder 108a and the second adsorption cylinder 108b, respectively. The compressed air generated from the compressor 10 is alternately supplied to the first adsorption cylinder body 108a and the second adsorption cylinder body 108b via the pipe 6 and the three-way switching valves 109a and 109b.

Zeolite as a catalyst adsorbent is stored in the first adsorption cylinder 108a and the second adsorption cylinder 108b, respectively. This zeolite is, for example, an X-type zeolite having a Si ₂ O ₃ / Al ₂ O ₃ ratio of 2.0 to 3.0, and at least 88% or more of this Al ₂ O ₃ tetrahedral unit is composed of lithium cations. By using the bonded one, the adsorption amount of nitrogen per unit weight can be increased. This zeolite preferably has a granule measurement value of less than 1 mm, and at least 88% of tetrahedral units are fused with lithium cations. By using zeolite, it becomes possible to reduce the amount of raw material air used for generating oxygen compared to the case of using other adsorbents. As a result, the compressor 10 for generating the compressed air and the decompressed air can be of a smaller type, and the noise of the compressor 10 can be reduced.

  As shown in FIG. 1, an equal pressure valve 107 including a check valve, a throttle valve, and an on-off valve is connected to the outlet side of the first adsorption cylinder body 108a and the second adsorption cylinder body 108b. A pipe 8 to be joined is connected to the downstream side of the equal pressure valve 107, and a product tank 111 is connected to the pipe 8. The product tank 111 is a container for storing oxygen having a concentration of about 90% or more generated by separation in the first adsorption cylinder 108a and the second adsorption cylinder 108b.

  As shown in FIG. 1, a pressure regulator 112 is connected to the downstream side of the product tank 111, and the pressure regulator 112 is a regulator that automatically adjusts the oxygen pressure on the outlet side of the product tank 111 to a constant level. . A zirconia-type or ultrasonic-type oxygen concentration sensor 114 is connected to the downstream side of the pressure regulator 112, and the oxygen concentration sensor 114 detects the oxygen concentration intermittently (every 10 to 30 minutes) or It is designed to be performed continuously.

As shown in FIG. 1, a proportional opening degree valve 115 is connected to the oxygen concentration sensor 114. This proportional opening valve 115 opens and closes in response to a setting button operation of the oxygen flow rate setting button 308 in accordance with a signal from the flow rate control unit 202 according to a command from the central control unit 200. An oxygen flow rate sensor 116 is connected to the proportional opening valve 115. A demand valve 117 is preferably connected to the oxygen flow sensor 116 via a decompression air circuit board for breathing synchronization control. The demand valve 117 passes through a sterilization filter 119 and passes through an oxygen outlet 9 of the oxygen concentrator 1. It is connected to the. By controlling the demand valve 117 and performing respiratory synchronization control, generally considering that the IE ratio (ratio of inspiratory time (seconds) to expiratory time (seconds)) is 1: 2, by respiratory synchronous control, The patient will have the same effect as supplying oxygen concentrated to 90% or more at substantially 5 L / min to 8 L / min.
The adapter 313 of the nasal cannula 314 is detachably connected to the oxygen outlet 9 . Adapter 313 is connected to nasal cannula 314 via tube 315. The patient can inhale oxygen concentrated to about 90% or more through the nasal cannula 314, for example, at a maximum flow rate of 3 L / min.

Next, the power supply system shown in FIG. 1 will be described.
A connector 430 of an AC (commercial AC) power source shown in FIG. 1 is electrically connected to a switching regulator type AC adapter 419, and the AC adapter 419 rectifies the AC voltage of the commercial AC power source into a predetermined DC voltage. The built-in battery 228 is built in the bottom of the main housing 2. The external battery 227 is detachably provided via the connector 431. The power supply control circuit 226 is electrically connected to the connectors 430 and 431. The built-in battery 228 and the external battery 227 are rechargeable secondary batteries, and the built-in battery 228 can be charged by receiving power from the power supply control circuit 226. The external battery 227 can be charged by receiving power supply from the power supply control circuit 226. However, the external battery 227 is normally repeatedly charged using a battery charger separately prepared.

  Thus, the central control unit 200 in FIG. 1 controls the power supply control circuit 226 so that the power supply control circuit 226 receives the power supply from the AC adapter 419 and operates from the built-in battery 228. Automatically switched to one of three power supply states, a second power supply state that operates in response to the supply of power and a third power supply state that operates in response to the power supply from the external battery 227 Can be used. The built-in battery 228 and the external battery 227 are preferably lithium ion or lithium hydrogen ion secondary batteries that have little memory effect during charging and can be fully charged even during recharging, but may be conventional nickel cadmium batteries or nickel metal hydride batteries. Further, in preparation for an emergency, the external battery 227 may be configured as a box of, for example, an AA battery that can be obtained anywhere.

The central control unit 200 in FIG. 1 is electrically connected to a motor control unit 201 and a fan motor control unit 203. The central control unit 200 stores a program for switching to an optimal operation mode according to the amount of oxygen to be generated. The motor control unit 201 and the fan motor control unit 203 automatically drive the compressor 10 and the blower fan 5 at a high speed when generating a large amount of oxygen in response to a command from the central control unit 200. Control is performed to rotate the compressor 10 and the blower fan 5 at a low speed.

  The central control unit 200 incorporates a ROM (read-only memo) that stores a predetermined operation program. The central control unit 200 includes an external storage device 210, a volatile memory, a temporary storage device 208, and a real-time clock. The circuit 207 is electrically connected. The central control unit 200 can access the stored contents by connecting to the communication line 444 or the like via the external connector 433.

  Further, the control for controlling the three-way switching valves 109a and 109b and the equal pressure valve 107 shown in FIG. 1 to be turned on and off so that unnecessary gas in the first adsorption cylinder 108a and the second adsorption cylinder 108b is desorbed. A circuit (not shown), the flow rate control unit 202, and the oxygen concentration sensor 114 are electrically connected to the central control unit 200. The flow control unit 202 drives and controls the proportional opening valve 115, the flow sensor 116, and the demand valve 117. In addition, an oxygen flow rate setting button 308, a display unit 128, and a power switch 306 are electrically connected to the central control unit 200 shown in FIG. The oxygen flow rate setting button 308 can set the oxygen flow rate every time the oxygen concentrated to, for example, about 90% or more is operated in a step of 0.01 L from 0.25 L (liter) per minute to 3 L at maximum. In order to supply 90% or higher concentration of oxygen to the patient at substantially 5 L / min by respiratory synchronization control, a synchronization mode selection switch (not shown) that can be operated by the patient is preferably provided. When the breathing synchronization control is operating, the display unit 128 uses a display device such as a liquid crystal display, for example. On the display unit 128, for example, display items such as an operation lamp, an oxygen lamp, a “tuning mode”, a charging lamp, a “remaining battery amount”, an “integrated time”, and an “oxygen flow rate” can be lit and displayed. When the respiration synchronization control is operating, the “synchronization mode” display is lit in green, for example.

  Next, a preferred structural example of the compressor 10 shown in FIG. 1 will be described with reference to FIGS. Here, the weight of the compressor 10 is suppressed to about 1 kg. FIG. 2 is a perspective view showing the compressor 10, and FIG. 3 is a perspective view in which a part of the compressor 10 shown in FIG. 2 is cut away. 4 is a longitudinal (V direction) cross-sectional view showing the internal structure of the compressor 10 of FIG.

  The compressor 10 shown in FIGS. 2 to 4 generates only compressed air by the positive pressure fluctuation adsorption method (PSA) by generating only compressed air as already described, and the first adsorption cylinder 108a shown in FIG. 2 It sends into the adsorption cylinder 108b, and the nitrogen in compressed air is adsorbed by the adsorbent in the first adsorption cylinder 108a and the second adsorption cylinder 108b. The compressor 10 is a four-head compressor having a synchronous motor as the drive motor 11 and four heads. A first pump unit 21 is provided on one side of the synchronous motor 11, and a second pump unit 22 is provided on the other side of the drive motor 11. That is, the drive motor 11 is disposed between the first pump unit 21 and the second pump unit 22.

  The drive motor 11 is, for example, a single-phase four-pole AC synchronous motor. The first pump part 21 and the second pump part 22 have a substantially symmetrical shape, and the first pump part 21 and the second pump part 22 are reciprocating driven by one output shaft 15 of the drive motor 11. It is a drive pump. The rotor of the drive motor 11 is rotated by a rotating magnetic field created from an AC waveform. The drive motor 11 is operated as a DC (direct current) brushless motor by a rectification bridge circuit at the time of start-up when using an AC power source, and switched to an AC synchronous motor without using a rectification bridge circuit at the time of operation reaching the synchronous rotational speed. It rotates at the same speed as the rotating magnetic field. Thus, the motor efficiency during the steady operation is increased to about 80%, and the power consumption is reduced.

  First, the structure of the drive motor 11 will be described with reference to FIGS. 3 and 4. The drive motor 11 shown in FIGS. 3 and 4 is an outer rotor type motor, and is disposed between the first pump portion 21 and the second pump portion 22, and as shown in FIG. A rotor (rotor) 13 and a stator (stator) 14 are provided. The rotor 13 and the stator 14 are assembled in the housing 12. The housing 12 includes a cylindrical outer case 12A, and left and right lid members 12B and 12C that cover an opening on one end side and an opening on the other end side of the outer case 12A.

  The rotor 13 shown in FIG. 4 has a rotor case (magnet case) 23 and a ring-shaped permanent magnet 24. The rotor case 23 is formed coaxially with the output shaft 15, and the output It is integrally fixed to the outer peripheral surface of the shaft 15. The permanent magnet 24 is fixed to the inner peripheral surface of the rotor case 23. The output shaft 15 is rotatably supported by bearings 12F and 12G of the lid members 12B and 12C. The stator 14 has a stator core 25 and a stator magnetic pole 26. The output shaft 15 passes through the center hole 25H of the stator core 25. Four stator magnetic poles 26 are arranged at intervals of 90 degrees. In addition, a coil bobbin in which a motor board and a motor coil are housed is assembled in the vicinity of the stator magnetic pole 26.

  Since a synchronous motor is preferably used as the drive motor 11, the rotation speed of the output shaft 15 can be made constant even when the power supply voltage fluctuates, and the first pump unit 21 and the second pump unit 22 can be rotated stably. Can be driven by numbers. That is, since the drive motor 11 can rotate at the synchronous rotation speed, power consumption can be reduced as compared with the induction motor. Accordingly, the first pump portion 21 and the second pump portion 22 shown in FIG. 1 can stably supply the compressed air to the first adsorption cylinder body 108a and the second adsorption cylinder body 108b, and the first adsorption cylinder body 108a The second adsorption cylinder 108b can stably supply oxygen concentrated to 90% or more, for example, at an oxygen flow rate set in a range of 0.5 L / min to 3.0 L / min.

  Next, the structures of the first pump portion 21 and the second pump portion 22 of the compressor 10 will be described with reference to FIGS. As shown in FIGS. 2 and 3, the compressor 10 includes a first pump unit 21 and a second pump unit 2, and the first pump unit 21 is disposed on one side of the drive motor 11, and the second pump unit 21. The pump unit 22 is disposed on the other side of the drive motor 11. The first pump unit 21 and the second pump unit 2 have a substantially bilaterally symmetric shape with respect to a virtual center line CK (see FIG. 4) orthogonal to the rotation center axis CL of the output shaft 15. As shown in FIGS. 2 and 3, the first pump unit 21 includes a first head unit 31, a second head unit 32, and a case unit 33. Similarly, the second pump part 22 includes a third head part 41, a fourth head part 42, and a case part 43.

  Here, the 1st head part 31, the 2nd head part 32, the 3rd head part 41, and the 4th head part 42 which are shown in FIG. 4 are demonstrated. As shown in FIG. 4, the first head unit 31 is installed at one end of the case unit 33, and the second head unit 32 is installed at the other end of the case unit 33. A first end portion 15A of the output shaft 15 of the drive motor 11 passes through an intermediate portion of the case portion 33, and the first end portion 15A of the output shaft 15 is rotatably supported by a bearing 33B of the case portion 33. ing. The first head portion 31 includes a cylinder portion 31S, a head cover 31H, and a piston 31P. The piston 31P is attached to the connecting rod 31C. The connecting rod 31 </ b> C is attached to the first end portion 15 </ b> A of the output shaft 15 using a bearing. The second head portion 32 includes a cylinder portion 32S, a head cover 32H, and a piston 32P. The piston 32P is attached to the connecting rod 32C. The connecting rod 32C is attached to the first end 15A of the output shaft 15 using a bearing.

  As shown in FIG. 4, the third head portion 41 is installed at one end portion of the case portion 43, and the fourth head portion 42 is installed at the other end portion of the case portion 43. A second end portion 15B of the output shaft 15 of the drive motor 11 passes through an intermediate portion of the case portion 43, and the second end portion 15B of the output shaft 15 is rotatably supported by a bearing 43B of the case portion 43. ing. The third head portion 41 includes a cylinder portion 41S, a head cover 41H, and a piston 41P. The piston 41P is attached to the connecting rod 41C. The connecting rod 41C is attached to the second end 15B of the output shaft 15. The fourth head portion 42 includes a cylinder portion 42S, a head cover 42H, and a piston 42P. The piston 42P is attached to the connecting rod 42C. The connecting rod 42 </ b> C is attached to the second end 15 </ b> B of the output shaft 15.

  As described above, the compressor 10 is connected to the drive motor 11 having one output shaft 15 and the first end portion 15A of the output shaft 15 of the drive motor 11, and operates by the rotation of the output shaft 15. It is connected to the first pump portion 21 that sucks air to generate compressed air and the second end portion 15B of the output shaft 15 of the drive motor 11, and operates by the rotation of the output shaft 15 to suck the raw material air. And a second pump unit 22 that generates compressed air.

4, when the output shaft 15 continuously rotates around the rotation center axis CL, the pistons 31P and 32P of the first pump unit 21 reciprocate in the V direction, and the pistons 41P and 42P of the second pump unit 22 Reciprocates in the V direction. The two pistons of the first head portion 31 and the second head portion 32 are horizontally opposed pistons that reciprocate in opposite directions. That is, the 1st pump part 21 has the 1st head part 31 which has the 1st piston 31P, and the 2nd head part 32 which has the 2nd piston 32P, and the 1st head part 31 and the 2nd head part 32 are The first piston 31P and the second piston 32P are oppositely disposed so as to reciprocate in the opposite direction along the V direction. Similarly, the 2nd pump part 22 has the 3rd head part 41 which has the 3rd piston 41P, and the 4th head part 42 which has the 4th piston 42P, and the 3rd head part 41 and the 4th head part 42 is horizontally opposed to reciprocate the third piston 41P and the fourth piston 42P in the opposite direction along the V direction.

  Moreover, in the suction process in which the first pump unit 21 sucks the raw material air, a compression process is performed in which the air sucked by the second pump unit 22 is compressed to generate compressed air, and the air sucked by the first pump unit 21 is used. In the compression process of compressing and generating compressed air, the second pump unit 22 performs a suction process of sucking the raw material air. As shown in FIGS. 4 and 3, the pistons 31 </ b> P and 32 </ b> P of the first pump unit 21 and the pistons 41 </ b> P and 42 </ b> P of the second pump unit 22 reciprocate in opposite phases. When the piston compresses air to generate compressed air, a load is applied to the output shaft 15, and when the piston sucks air, the output shaft 15 is not loaded as compared with the case of compression. In the present embodiment, as described above, the left side pistons 31P and 32P and the right side pistons 41P and 42P in FIG. The fluctuation of the load applied to the output shaft 15 is made constant. That is, the load balance when the first pump unit 21 and the second pump unit 22 generate compressed air can be adjusted to be constant.

  Therefore, for example, as shown in FIG. 4, when the pistons 31P and 32P are positioned at the top dead center and the raw air in the cylinders 31S and 32S is compressed, the pistons 41P and 42P are positioned at the bottom dead center. Thus, the raw material air in the cylinders 41S and 42S is inhaled. Conversely, when the pistons 41P and 42P are located at the top dead center and the raw material air in the cylinders 41S and 42S is compressed, the pistons 31P and 32P are located at the bottom dead center and the cylinder 31S. , 32S enters the state in which the raw material air is sucked. As a result, unlike the embodiment of the present invention, the present invention is implemented in comparison with the case where the left pistons 31P and 32P and the right pistons 41P and 42P are in the same phase in which the compression operation and the suction operation are simultaneously performed. As shown in the figure, the load applied to the output shaft 15 of the drive motor 11 is kept constant by alternately shifting the compression operation and the suction operation of the left piston 31P, 32P and the right piston 41P, 42P to opposite phases. Can be reduced. By suppressing the load fluctuation to the drive motor 11, the power consumption of the drive motor 11 can be reduced.

Next, referring to FIG. 5 and FIG. 2, examples of the feed air introduction path and the compressed air discharge path after the feed air is compressed in the first pump part 21 and the second pump part 22 of the compressor 10. Will be explained.
FIG. 5 shows an outer shape of the compressor 10 by a two-dot chain line, a raw air introduction path 50 in the compressor 10 is shown by a solid line, and a compressed air discharge path 60 is shown by a broken line.
The raw material air introduction path 50 shown by a solid line in FIG. 5 has introduction ports 51A and 51B and introduction passages 52A and 52B. The introduction ports 51A and 51B are connected to the filter 3 of the intake port 2c through the internal pipe 4. The introduction port 51A and the introduction passage 52A are provided in the case portion 33 of the first pump portion 21, and the introduction passage 52A is formed along the V direction. The introduction port 51A is connected to the introduction passage 52A, the upper end portion of the introduction passage 52A communicates with the cylinder of the first head portion 31, and the lower end portion of the introduction passage 52A communicates with the cylinder of the second head portion 32. Yes.

  The introduction port 51B and the introduction passage 52B are provided in the case portion 43 of the second pump part 22, and the introduction passage 52B is formed along the V direction. The introduction port 51B is connected to the introduction passage 52B, the upper end portion of the introduction passage 52B communicates with the cylinder of the third head portion 41, and the lower end portion of the introduction passage 52B communicates with the cylinder of the fourth head portion 42. Yes. Thus, the raw air 70 can be supplied into the first head portion 31, the second head portion 32, the third head portion 41, and the fourth head portion 42 by the suction operation of the four pistons 31P, 32P, 41P, and 42P, respectively. .

  On the other hand, the discharge path 60 indicated by a broken line in FIG. 5 has discharge ports 61A and 61B and discharge passages 62A and 62B. The discharge ports 61A and 61B are connected to the first adsorption cylinder body 108a and the second adsorption cylinder body 108b via the pipe 6. The discharge port 61A and the discharge passage 62A are provided in the case portion 33 of the first pump portion 21, and the discharge passage 62A is formed along the V direction. The discharge port 61A and the discharge passage 62A are connected, the upper end of the discharge passage 62A communicates with the cylinder of the first head portion 31, and the lower end of the discharge passage 62A communicates with the cylinder of the second head portion 32. Yes.

  In FIG. 5, the discharge port 61 </ b> B and the discharge passage 62 </ b> B are provided in the case portion 43 of the second pump portion 22, and the discharge passage 62 </ b> B is formed along the V direction. The discharge port 61B is connected to the discharge passage 62B, the upper end portion of the discharge passage 62B communicates with the cylinder of the third head portion 41, and the lower end portion of the discharge passage 62B communicates with the cylinder of the fourth head portion 42. Yes. Thereby, the compressed air 80 compressed by the four pistons 31P, 32P, 41P, and 42P can be supplied to the first adsorption cylinder body 108a and the second adsorption cylinder body 108b via the pipe 6.

FIG. 6 is a longitudinal sectional view showing a structural example of the first pump unit 21 and the second pump unit 22. The first pump part 21 and the second pump part 22 have substantially the same structure.
As shown in FIG. 6, the case portion 33 of the first pump portion 21 has an introduction passage 52A and a discharge passage 62A. Similarly, the case part 43 of the second pump part 22 has an introduction passage 52B and a discharge passage 62B. FIG. 7 is an exploded perspective view showing, as an example, the structure of the first head unit 31 among the four first head units 31, the second head unit 32, the third head unit 41, and the fourth head unit 42. Here, the first head part 31, the second head part 32, the third head part 41, and the fourth head part 42 have substantially the same structure. Therefore, the structure of the first head portion 31 will be described as a representative.

  7 shows a head cover 31H of the first head portion 31, gaskets 91 and 92, an upper member 93, a reed valve member 94, and a lower member 95. The head cover 31H is securely and evenly fixed to the cylinder 31S by a plurality of bolts 96 with the gaskets 91 and 92, the upper member 93, the reed valve member 94, and the lower member 95 being sandwiched in the illustrated order. Can do. The gaskets 91 and 92 prevent leakage when the raw air is compressed. The gaskets 91 and 92 have an opening 99. The reed valve member 94 has two reed valves 94A and 94B. The upper member 93 has openings 93A and 93B, and the lower member 95 has openings 95A and 95B.

Next, an operation example of the oxygen concentrator 1 described above will be described. The central control unit 200 in FIG. 1 instructs the motor control unit 201, and the motor control unit 201 starts a synchronous motor that is the driving motor 11 of the compressor 10 , and the driving motor 11 rotates at a constant rotational speed. . Thereby, since the output shaft 15 of the driving motor 11 continuously rotates around the rotation center axis CL, the first pump portion 21 and the second pump portion 22 can be driven at a stable rotational speed. For this reason, the two pistons 31P and 32P of the first pump part 21 simultaneously repeat the air suction process and the compression process of compressing and discharging the compressed air, and at the same time, the two pistons 41P of the second pump part 22 42P repeats the compression process in which compressed air is compressed and discharged, and the air suction process.

As shown in FIGS. 4 and 3, the pistons 31P and 32P of the first pump portion 21 and the pistons 41P and 42P of the second pump portion 22 reciprocate in opposite phases. That is, for example, as illustrated in FIG. 4, when the pistons 31P and 32P are positioned at the top dead center and the raw air in the cylinders 31S and 32S is in a compressed state, the pistons 41P and 42P are positioned at the bottom dead center. Thus, the raw material air in the cylinders 41S and 42S is inhaled. Contrary to the state shown in FIG. 4, when the pistons 41P and 42P are located at the top dead center and the raw material air in the cylinders 41S and 42S is in the compressed state, the pistons 31P and 32P are located at the bottom dead center. Thus, the raw material air in the cylinders 31S and 32S is inhaled.

  Thus, when the piston compresses air to generate compressed air, a load is applied to the output shaft 15, and when the piston sucks air, the load is applied to the output shaft 15 compared to the case where the piston compresses the air. It does not take. By repeating the compression process and the suction process alternately so that the first pump section 21 and the second pump section 22 are in opposite phases, a constant load is always applied to the output shaft 15 during operation. The load balance applied to the output shaft 15 of the motor 11 can be adjusted to be constant. Since the first pump portion 21 and the second pump portion 22 are provided symmetrically on the first end portion 15A and the second end portion 15B of the output shaft 15, respectively, the pump portion is provided at one end portion of the output shaft. Compared with the case where it is provided, it is possible to reduce the load fluctuation applied to the output shaft 15 of the driving motor 11 during operation and reduce the power consumption. In particular, in the case of a portable or mobile oxygen concentrator, it is possible to reduce the size of the on-board battery that is required due to the demand for weight reduction and size reduction.

Since heat is generated when the compressor 10 in FIG. 1 compresses raw material air to generate compressed air, the compressor 10 is cooled by the blower fan 5 shown in FIG. By cooling the compressed air in this way, zeolite, which is an adsorbent whose function is reduced at high temperatures, can sufficiently function as an adsorbent for generating oxygen by adsorption of nitrogen. It can be concentrated to a degree or more. Compressed air passes through the first adsorbing cylinder 108a and the second adsorbing cylinder 108b through the pipe 6 and the three-way switching valves 109a and 109b, and adsorbs nitrogen to generate oxygen. Is done. The product tank 111 stores oxygen having a concentration of about 90% or more generated by separation.

The oxygen concentration sensor 114 in FIG. 1 detects the oxygen concentration from the product tank 111. The proportional opening valve 115 opens and closes in conjunction with the oxygen flow rate setting button 308. Then, oxygen is supplied to the nasal cannula 314 through the sterilization filter 119 and the oxygen outlet 9 of the oxygen concentrator 1. Thereby, the patient can inhale oxygen concentrated to about 90% or more through the nasal cannula 314, for example, at a maximum flow rate of 3 L / min.

In the above-described embodiment of the present invention, the positive pressure fluctuation adsorption method (PSA) using only compressed air sends only compressed air into the adsorption cylinder and adsorbs nitrogen. Therefore, the positive and negative pressure fluctuation adsorption method using compressed air and reduced pressure air ( Compared with VPSA), there is an advantage that the structure of the compressor can be simplified.
In the compressor 10, the first pump unit 21 is disposed on one side of the drive motor 11, and the second pump unit 22 is disposed on the other side of the drive motor 11. The 1st pump part 21 and the 2nd pump part 2 have a substantially right-and-left symmetrical shape, and have a structure which can balance the right-and-left weight.

The left pistons 31P and 32P and the right pistons 41P and 42P in FIG. 4 on the output shaft 15 reciprocate so as to be in opposite phases so that the load balance applied to the drive motor 11 is as constant as possible. Can be adjusted. Thereby, the load fluctuation applied to the output shaft of the motor during operation can be reduced to reduce power consumption. Since the drive motor 11 is preferably used as the drive motor, the rotation speed of the output shaft 15 can be made constant even when the power supply voltage fluctuates, and the first pump unit 21 and the second pump unit 22 are stabilized. It can be driven at the rotational speed. The drive motor 11 rotates at the synchronous rotation speed, and can reduce power consumption compared with the induction motor.
In particular, in a portable oxygen concentrator that has been reduced in size and weight, oxygen that has been concentrated to 90% or more can be continuously supplied up to 3 L / min, and power consumption can be reduced. Moreover, if the breathing synchronization function is operated, oxygen concentrated to 90% or more can be supplied substantially at 5 L / min to 8 L / min.

By the way, the present invention is not limited to the above-described embodiments, and various modifications and changes can be made to the present invention, and various modifications can be made within the scope described in the claims.
For example, the oxygen concentrator is not limited to the illustrated portable oxygen concentrator, but may be a stationary oxygen concentrator. The oxygen concentrator shown in FIG. 1 generates oxygen by a positive pressure fluctuation adsorption method (PSA) using only compressed air. However, the oxygen concentrator is not limited thereto, and oxygen is produced by a positive / negative pressure fluctuation adsorption method (VPSA) using compressed air and reduced pressure air. May be generated. In this positive / negative pressure fluctuation adsorption method, the zeolite in the adsorption cylinder is more actively washed by reducing the pressure using the decompressed air in addition to the compressed air. The driving motor for the compressor 10 shown in the figure is, for example, a synchronous motor of 3 L class (meaning that oxygen concentrated to 90% or more can be supplied continuously at 3 L / min), but is not limited to this, and other types of motors are used. It may be a motor. The drive motor may be a single-phase AC induction motor.

  The first pump unit 21 and the second pump unit 22 are horizontally opposed so that the pistons reciprocate in opposite directions, but the present invention is not limited to this, and two pistons may be arranged in a V shape, for example. . Regarding the supply of the raw material air to the first pump part 21 and the second pump part 22, the first head part 31 and the second head part 32 of the first pump part 21, and the third head part 41 of the second pump part 22. This can be done by connecting a common connecting pipe for suction between the first head part 42 and the fourth head part 42. The compressed air generated from the first pump unit 21 and the second pump unit 22 is discharged from the first head unit 31 and the second head unit 32 of the first pump unit 21 and the third pump unit 22. This can be done by connecting a common connecting pipe for discharge between the head part 41 and the fourth head part 42.

DESCRIPTION OF SYMBOLS 1 ... Oxygen concentrator, 2 ... Main housing, 2c ... Intake port, 3 ... Filter, 4 ... Piping, 6 ... Piping, 10 ... Compressor, 11 ... Drive motor, 15 ... output shaft, 21 ... first pump part, 22 ... second pump part, 31 ... first head part, 32 ... second head part, 31P, 32P ... piston, 41 ... 3rd head part, 42 ... 4th head part, 41P, 42P ... piston, 33, 43 ... case part, 70 ... raw material air, 80 * ..Compressed air, 108a ... first adsorption cylinder (adsorption member), 108b ... second adsorption cylinder (adsorption member), 109a, 109b ... 3-way switching valve, 111 ... product tank , 201 ... motor control unit, 314 ... nasal cannula

Claims (4)

An oxygen concentrator comprising a compressor that compresses raw material air to generate compressed air, and an adsorbing member that contains an adsorbent that adsorbs nitrogen from the compressed air,
The compressor is
In the upright state, the rotor and stator of the drive motor are accommodated in the housing located in the center, and extend horizontally through the housing, and are exposed to the left exterior and the right exterior of the housing, respectively. A drive motor comprising a first end that is the left end of the output shaft protruding so as to have a second end that is the right end of the output shaft ;
Is connected to the first end of the output shaft of the driving motor, a first pump for generating compressed air by suction feed air operated by the rotation of the output shaft,
A second pump unit connected to the second end of the output shaft of the drive motor and operating by rotation of the output shaft to suck in raw material air and generate compressed air;
The first pump part and the second pump part are arranged at symmetrical positions on both right and left ends of the output shaft,
Each pump portion is provided at a position that is the same distance away from each other along the direction orthogonal to the one direction at the symmetrical positions of the left and right ends of the output shaft, and each along the orthogonal direction. An oxygen concentrator having a reciprocating piston.   The first pump part includes a first head part having a first piston and a second head part having a second piston, and the first head part and the second head part include the first piston and the second piston part. The second pump part is disposed opposite to reciprocate the second piston in the opposite direction, and the second pump part has a third head part having a third piston and a fourth head part having a fourth piston, 2. The oxygen concentration according to claim 1, wherein the third head portion and the fourth head portion are arranged to face each other so as to reciprocate the third piston and the fourth piston in opposite directions. apparatus.   In the suction process in which the first pump part sucks the raw material air, a compression process is performed in which the air sucked by the second pump part is compressed to generate the compressed air, and the first pump part sucks the air. 3. The oxygen concentrator according to claim 1, wherein in the compression step of compressing air to generate the compressed air, the second pump unit performs a suction step of sucking the raw material air.   The oxygen concentrator according to any one of claims 1 to 3, wherein the driving motor is an AC synchronous motor.

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